Mobile room dividing structure

ABSTRACT

A room dividing structure wherein the lower end of a shiftable vertical partition has a projection extending into a guide groove of the floor and the upper end of the partition is connected with a runner movable along horizontal guide rails mounted on a vertically movable beam which is received in a groove of the ceiling. The beam carries two sealing strips and is movable by a motor or by a manually operated device, with and relative to the partition, between an uppermost position in which the bottom end face of the partition is lifted off the floor, an intermediate position in which the bottom end face of the partition rests on the floor, and a lowermost position in which it urges the sealing strips against the upper end face of the partition as well as against two panels which flank the groove in the ceiling.

3,827,196 Aug. 6, 1974 MOBILE ROOM DIVIDING STRUCTURE [75] Inventor:Ernst Voegeli, Zurich, Switzerland [73] Assignee: Faltag AG, Altihausen(Thurgau),

Switzerland [22] Filed: Oct. 24, 1972 [2]] Appl. No.: 300,380

[30] Foreign Application Priority Data Oct. 23, I971 Switzerlandl6679/7l [52] U.S. Cl. 52/64 [51] Int. Cl E04b 1/343 [58] Field ofSearch 52/39, 64, 122; 160/200,

[56] References Cited UNITED STATES PATENTS 3,685,223 8/l972 Sherwood52/64 Primary Examiner-John E. Murtagh Attorney, Agent, or Firm-MichaelS. Striker 5 7 ABSTRACT A room dividing structure wherein the lower endof a shiftable vertical partition has a projection extending into aguide groove of the floor and the upper end of the partition isconnected with a runner movable along horizontal guide rails mounted ona vertically movable beam which is received in a groove of the ceiling.The beam carries two sealing strips and is movable by a motor or by amanually operated device, with and relative to the partition, between anuppermost position in which the bottom end face of the partition: islifted off the floor, an intermediate position in which the bottom endface of the partition rests on the floor, and a lowermost position inwhich it urges the sealing strips against the upper end face of thepartition as well as against two panels which flank the groove in theceiling.

20 Claims, 9 Drawing Figures Lia MOBILE ROOM DIVIDING STRUCTUREBACKGROUND OF THE INVENTION The present invention relates to roomdividing structures in general, and more particularly to improvements inroom dividing structures which employ one or more shiftable partitions.

The ever rising cost of land compels the builders of private homes,apartment dwellings and/or public and commercial establishments toutilize the space within a building with the highest possible degree ofefficiency. This involves the use of removable, shiftable or otherwisetransferable partitions which enable the builder to subdivide arelatively large room into two or more smaller chambers. The partitionsrender it possible to subdivide the interior of a freshly erected or theinterior of an existing building into any desired number of chambers inaccordance with the desires or plans of a particular owner or tenant.

A drawback of presently known mobile partitions or analogous roomdividers is that they are incapable of properly sealing the spaces atthe opposite sides thereof against the penetration or propagation offire, sound, odor and/or smoke. In many instances, stringent lawsregulating fire prevention, soundproofing and/or other othercharacteristics of walls in dwellings or in public or commercialestablishments prevent the builders from using mobile partitions becausethe presently known partitions cannot guarantee full compliance withsuch regulations.

As a rule, presently known room dividers employ partitions which areslidable along the floor and/or along the ceiling to assume a selectedposition. Such mounting invariably entails the provision of at leastsome clearances between a slidable partition on the one hand the ceilingand/or floor on the other hand. The clearances permit the propagation ofsound as well as the penetration of odors and smoke from a chamber atthe one side to a chamber at the other side of the installed partition,or vice versa. Attempts to eliminate such clearances, once thepartitition has been moved to a desired position, include theutilization of flexible sealing strips consisting of rubber or otherelastomeric material which are secured to the partition in deformedcondition so as to bear against the ceiling and/or against the floor.Sealing strips are rather inexpensive and can constitute reasonablysatisfactory proofing means against the passage of odors or smoke;however, their soundproofing characteristics are quite unsatisfactory,especially if they consist of relatively thin and hence readily flexibleelastomeric material which can follow the outline of a ceiling or floor.It was found that flexible elastomeric strips are only capable ofinterrupting the propagation of a very narrow range of highest soundfrequencies so that their qualities regarding the proofing againstspeech sounds are practically. nil.

It was further proposed to eliminate the clearances between a mobilepartition and the ceiling and/or floor of a dwelling or the like byresorting to sealing bolts which must be mechanically pressed againstthe partition as well as against the adjacent part of the floor orceiling. The soundproofing effect of such bolts is superior to that ofelastomeric strips but is still far from being satisfactory for a numberof purposes, especially in dividers for use in private homes, apartmentsand office buildings. Furthermore, certain these sealing bolts embodyinserts which adversely affect the soundproofing quality of thepartition. Still further, all of the aforediscussed prior proposalsexhibit the serious drawback that the sealing action is more or lessaccidental because it is overly dependent on the smoothness of theceiling or floor surfaces, on the flexibility of elastic strips, on themechanical force which is being applied to the bolts, and/or otherunpredictable factors. Such absence of reliable sealing action not onlyaffects the soundproofing characteristics but is even more likely toadversely affect the ability of the room divider to prevent thepropagation of odors and/or smoke.

SUMMARY OF THE INVENTION An object of the invention is to provide anovel and improved room dividing structure which utilizes one or moremobile partitions and whose soundproofing characteristics are farsuperior to those or presently known room dividers.

Another object of the invention is to provide a room dividing structurewhich is capable of reliably preventing the penetration of smoke and/orodors from the one side to the other side of a properly installedpartition.

A further object of the invention is to provide a room dividingstructure which does not adversely affect the appearance of theenclosure wherein the structure is being put to use, which can bemanipulated by hand or by a motor, which can properly seal along the.ceiling as well as along the floor, and which can be installed in newlyerected buildings as well as in existing dwellings.

An additional object of the invention is to provide novel and improvedmeans for soundproofing the region between the ceiling and/or floor anda mobile partition.

Still another object of the invention is to provide novel and improvedmeans for guiding and supporting a mobile partition which forms part ofthe improved room dividing structure.

A further object of the invention is to provide novel and improved meansfor establishing or terminating a sound-, smokeand odor-proof connectionbetween a partition and the ceiling and/or floor of a dwelling or thelike.

The invention is embodied in a room or an analogous enclosure in aprivate, commercial or public building which includes a first wallmember constituting the ceiling, a second wall member constituting thefloor, a partition extending between the first and second wall membersand registering with an elongated groove pro vided in one of the walls,an elongated sealing unit provided in the groove of the one wall forup-and-down movement therein, coupling means for connecting the sealingunit with the partition so as to allow for up-anddown movement of thesealing unit with and relative to the partition, and means for movingthe sealing unit up and down between a first position in which thepartition is spaced apart from the other wall and is movable relative tothe sealing unit in the longitudinal direction of the groove, a secondposition in which the partition sealingly engages the other wall, and athird position in which the partition continues to sealingly engage theother wall while the sealing unit bears against the partition andpreferably also against the one wall.

The sealing unit may include an elongated beamlike carrier which looselysupports two rigid or deformable sealing strips and is coupled to themoving means to disengage the sealing strips from the partition and fromthe one wall in the first position of the sealing unit. In the secondposition of the sealing unit, the carrier causes or allows the partitionto sealingly engage the other wall while the sealing strips may but neednot sealingly engage the partition and/or the other wall. In the thirdposition of the sealing unit, the partition is not only biased intopositive sealing engagement with the other wall (e.g., with the floor)but the sealing strips are simultaneously urged into sealing engagementwith the paneling flanking the groove in the one wall as well as againstthe adjacent end face of the partition.

The novel features which are considered as characteristic of theinvention are set forth in particular in the appended claims. Theimproved room divding structure itself, however, both as to itsconstruction and its mode of operation, together with additionalfeatures and advantages thereof, will be best understood upon perusal ofthe following detailed description of certain specific embodiments withreference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a schematic side elevationalview of a partition and a longitudinal vertical sectional view of thewall members in a room dividing structure which embodies the invention,the partition being shown in a position corresponding to the firstposition of the sealing unit;

FIG. la is a transverse vertical sectional view as seen in the directionof arrows from the line II of FIG. 1;

FIG. 2 is a view similar to that of FIG. 1 but showing the partition inthat position which corresponds to the second position of the sealingunit;

FIG. 2a is a transverse vertical sectional view as seen in the directionof arrows from the line IIII of FIG.

FIG. 3 is a view similar to that of FIG. 1 but showing the partition inthat position which corresponds to the third position of the sealingunit;

FIG. 3a is a transverse vertical sectional view as seen in the directionof arrows from the line IIIIII of FIG.

FIG. 4 is an enlarged view of the structure shown in the upper portionof FIG. la;

FIG. 5 is an enlarged view of the structure shown in the upper portionof FIG. 3a; and

FIG. 6 is a smaller-scale view of the mechanism for moving the sealingunit up and down relative to the ceiling, the view of FIG. 6 being takenin the direction of arrows as seen from the line VIVI of FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1-10, 2-2a and 3-3aillustrate a partition 1, having a thickness of between 2 /2 and 7 inch,preferably 4 inch, in two different positions relative to a bottom wallmember or floor A and a top wall member or ceiling B. The upper endportion la, which is vertically movable and elastically fixed in thepartition 1 is connected with a coupling device here shown as a runner 2which can travel lengthwise of guide rails 8 (FIG. 4) provided in avertically movable carrier beam 3. The

carrier beam 3 can descend to thereby displace and stress two elongatedsealing strips 4, made preferably of wood and/or aluminum profile. Theceiling B is formed with a groove D for the carrier beam 3 and sealingstrips 4, and the ceiling includes panels 5 which flank the groove D.The floor A is also formed with a groove, shown at 6, and the lower endportion of the partition 1 has one or more projections 7 which extendinto the groove 6.

In FIGS. 1 and 1a, the partition 1 is shown in a lifted position inwhich it can be readily shifted in the longitudinal direction of thegrooves D and 6. A scaling lines 10a which is recessed into the lowerend face of the partition 1 is thereby lifted above the surface of thefloor A.

In FIGS. 2 and 2a, the partition 1 has been lowered with the carrierbeam 3 so that the liner 10a sealingly engages the floor A at both sidesof the groove 6.

In FIGS. 3 and 3a, the carrier beam 3 has been caused to descendrelative to the lowered partition 1 whereby the beam urges the sealingstrips 4 against sealing strips 9, made preferably of felt, (FIG. 4) onthe panels 5 and also against a sealing liner 10 (FIGS. 4, 5) which isrecessed into the upper end face of the partition 1. The pairs ofsealing strips 4 and 9 are mirror symmetrical to each other withreferecne to the central longitudinal vertical plane of the partition 1.

The sealing liners 10, 10a, may consist of elastomeric material or feltand their width preferably equals or is only slightly less than thethickness of the partition 1.

FIG. 4 shows in detail the structure at the uper end of the partition 1and in the groove D of the ceiling B. The carrier beam 3 supports theguide rails 8 which can be secured thereto by screws or by analogousfasteners. The coupling device or runner 2 of the partition 1 has wheels2a which can roll along the upper end faces of the guide rails 8. Thecarrier beam 3 further supports the sealing strips 4 which may but neednot adhere to inclined biasing plates 11 having a T-shaped profile andsecured to the beam 3 by screws 12 or like fasteners. The biasing plates11 preferably make an angle of 45 with a horizontal plane which isnormal to the general plane of the partition 1. The sealing strips 9flank the sealing strips 4 and are secured to adjoining panels 5 of theceiling B at the open lower end of the groove D. The sealing strips 4are loosely coupled to the beam 3 only by the shanks of the connectingscrews 12.

As mentioned above, a movement of the carrier beam 3 from the uppermostposition shown in FIGS. 1, 1a and 4 to the lowermost position shown inFIGS. 3, 3a and 5 takes place in two stages. The first stage isterminated when the sealing lines 10a of the partition 1 rests on thefloor A (this is the sealing or lowermost position of the partition).The second state ends when the carrier beam has completed its downwardmovement relative to the partition 1 whereby the strips 4 bear againstthe adjacent strips 9 as well as against the adjacent portions of thesealing liner 10, assisted by the elastic force of the upper end portion1a.

The plates 11 subject the two sealing strips 4 to identical stresses(see FIG. 5) so that the strips 4 abut against the entire inner surfacesof the adjacent strips 9 and that the entire bottom surfaces of thestrips 4 bear against the adjacent portions of the liner 10 on thepartition 1. The thus obtained acoustic barrier is represented by thearrows l3, l4, l5 and 16. The arrow 13 shows the lowermost 'part of thebarrier which is formed by all layers of the partition 1 below thesealing liner 10. The next higher part of the barrier (arrow 14) isformed by the two sealing strips 4. This part of the barrier is just asimpermeable to sound as the part formed by the partition 1. The width ofthis second part differs from the width of the first part only by thewidth of the clearance which is provided between the sealing strips 4 toaccommodate the coupling device or runner 2. The next higher part (arrow15) of the acoustic barrier is formed by the sealing strips 4 and plates11. The uppermost part of the barrier bypasses the sealing strips 4 butmust extend through the panels 5 flanking the sealing strips 9 in thegroove D of the ceiling B. It will be noted that the width of allportions of the acoustic barrier equals or-at least approximates thethickness of the partition 1. This insures that the noise-suppressingaction in the region above the sealing liner 10 is just as satisfactoryas the noise-suppressing action of the partition 1. Moreover, thesealing elements 4, 9 and 10 prevent the penetration of sound into thespaces between the layers of the partition 1 as well as into the endfaces of such layers below the sealing liner 10. Also, the seal ingelements prevent the propagation of sound from layer to layer bycreating what may be termed an internal short circuit. Such internalshort circuit is especially important if a relatively thin layer of thepartition 1 (see the layer 17 in FIG. 4) blocks sound at a certainfrequency but can be bypassed along its edges by sound which istransmitted by air.

FIG. 4 shows that, when the carrier beam is in the fully liftedposition, the bottom surfaces of the sealing strips 4 are flush orsubstantially flush with the underside of the ceiling B. This means thatthe sealing strips 4 conceal the strips 9 while the outer layers of thepartition 1 conceal the sealing liner 10 which latter is preferablyrecessed into the upper end face of the partition. The material of thesealing strips 4 may be the same as that of the panels 5. This insuresthat, when the partition 1 is moved lengthwise from a first position toa second position, the ceiling B exhibits only a relatively narrowportion of the groove B, namely, the portion between the sealing strips4 for the runner 2. Since the strips 4 can be machined or otherwisefinished to have an eye-pleasing appearance, the unfilled portion of thegroove D does not adversely affect the appearance of the room whereinthe partition 1 is put to use.

The means for moving the partition 1 and the carrier beam 3 relative tothe floor A and ceiling B is shown in FIGS. 4 and 6. The uppermost partof the groove D receives a U-shaped supporting rail 20 for a series ofhorizontal pivot members 19 carrying one-armed levers 18. The levers 18are further pivotably connected to horizontal rods 21, coupled the oneto the other by means of bows, to a feed screw 22 which can be rotatedby a handwheel 22a (or a motor, not shown) to move the rod 21 lengthwisein or counter to the direction indicated by the arrows shown in FIG. 6.The carrier beam 3 has motion receiving projections 23 which can bereceived in notches 18a of the levers 18. The levers 18 can be pivotedto such an extent that the carier beam 3 moves between the positions ofFIGS. la and 3a and through the intermediate position of FIG. 2a. It ispreferred to provide the carrier beam 3 with a number of equidistantprojections 23 and to provide an equal number of levers 18 so that thebeam 3 can receive lifting forces at a number of points.

It is clear that the carrier beam 3 can be raised and lowered by otherlifting or displacing means, for example, by wedge-like cams (not shown)slidably mounted on the supporting rail 20 to engage the projections 23from below whereby the projections 23 act not unlike followers whichtrack the inclined faces of the respective cams. Also, each of theprojections 23 can be provided with a vertical feed screw mating with adiscrete spindle nut, and all of the spindle nuts can be rotatedsimultaneously through the intermediary of an endles chain or the like.

It is equally within the purview of the invention to mount the carrierbeam 3 in the groove 6 of the floor A and to configurate the groove D insuch a way that it can receive and guide the projection or projections 7of the partition 1. This would merely amount to a turning of thestructure shown in FIGS. 1 to 5 upside down. The means for moving thecarrier beam 3 would then lift the liner 10a into sealing engagementwith the ceiling B prior to complete liftng of the carrier beam 3 tomove the strips 4 into sealing engagement with the liner 10 (which isthen located at the underside of the partition). The soundproofingaction of the liner 10a at the lowrer or upper end of the partition 1 isjust as satisfactory as that of the liner 10.

If the feed screw 22 of FIG. 6 is rotated by a reversible electric motor(not shown), the circuit of the motor preferably includes limit switcheswhich are actuated by the partition 1 and/or carrier beam 3 to arrestthe motor when the beam reaches the position of FIG. 4 or FIG. 5. Thecontrol means for the motor may further include a set of pushbuttons orswitches which are actuatable to set the motor in motion, either to movethe carrier beam 3 from the position of FIG. 4 to that of FIG. 5 or viceversa.

The parts 3, 4, 8, l1 and 12 together constitute a sealing means or asealing unit which is movable with as well as relative to thepartition 1. The extent to which the sealing unit can move relative tothe partition 1 depends on the deformability of sealing strips 4 andalso on the height of the runner 2.

An important advantage of the improved room dividing structure is thatthe grooves which must be provided to allow for lengthwise shifting ofthe partition can be sealed just as satisfactorily as if the partitionwere permanently connected to the wall members A and B. Also, thesoundproofing action of the sealing elements is at least as satisfactoryas the soundproofing qualities of the partition, and such sealingelements are just as effective against the passage of smoke and/orodors. The partition 1 may be provided with one or more layers offireproofing material, and such layers can extend all the way betweenthe underside of the ceiling B and the upper side of the floor A. Theroom dividing structure is relatively simple and eye-pleasing, and thepartition and the carrier beam can be moved up and down by means of asimple, compact and rugged mechanism. Such mechanism can be used forsimultaneous lifting or lowering of two or more coplanar partitions andof the associated carrier beam. Thus, a single handwheel or a singlemotor can be used to change the position of a single partition or of twoor more partitions which together constitute a mobile dividing wall.

Without further analysis, the foregoing will 'sofully reveal the gist ofthe present invention that others can, by applying current knowledge,readily adapt it for various applications without omitting featureswhich fairly constitute essential characteristics of the generic andspecific aspects of my contribution to the art and, therefore, suchadaptations should and are intended to be comprehended within themeaning and range of equivalence of the claims.

What is claimed as new and desired to be protected by Letters Patent isset forth in the appended 1. In a room or an analogous enclosure, thecombination of an upper first wall; a lower second wall; a partitionextending between said walls, one of said walls having an elongatedgroove in register with said partition; an elongated sealing unitvertically movably installed in said groove; coupling means connectingsaid sealing unit with said partition so as to allow for verticalmovement of said sealing unit with and relative to said partition; andmeans for moving said sealing unit up and down between a first positionin which said partition is spaced apart from the other of said walls, asecond position in which said partition abuts against said other wall,and a third position in which said partition abuts against said otherwall and said sealing unit bears against said partition.

2. The combination of claim 1, wherein said coupling means is movablewith said partition in the longitudinal direction of said groove in thefirst position of said sealing unit.

3. The combination of claim 1, wherein said one wall is said first wall.

4. The combination of claim 3, wherein said sealing unit comprises anelongated carrier having at least one elongated guide member, saidcoupling means being movable with said partition lengthwise of saidguide member in said first position of said sealing unit.

5. The combination of claim 1, wherein said partition has apredetermined thickness and said sealing unit comprises an elongatedcarrier and two sealing strips mounted on said carrier and each having athickness at least substantially approximating half the thickness ofsaid partition.

6. The combination of claim 1, wherein said one wall includes two panelsflanking said groove and said sealing unit includes an elongated carrierand two elongated sealing strips mounted on said carrier and eachadjacent to one of said panels, said carrier including two plate-likebiasing elements each making an acute angle with the plane of saidpartition and each arranged to urge one of said sealing strips againstthe neighboring panel of said one wall in response to movement of saidsealing unit from said second to said third position thereof.

7. The combination of claim 6, wherein said sealing strips have inclinedfirst surfaces abutting against the respective biasing elements andsecond surfaces abutting against said partition in said third positionof said sealing unit.

8. The combination of claim 1, wherein said sealing unit comprises anelongated carrier, two sealing strips and means for movably connectingsaid sealing strips to said carrier so as to allow for sidewise movementof said sealing strips against said one wall in response to movement ofsaid sealing unit to said third position thereof.

9. The combination of claim 1, wherein said partition has first andsecond end faces, respectively, adjacent to said first and second wallsand first and second sealing liners respectively applied to said firstand second end faces thereof.

10. The combination of claim 9, wherein at least one of said liner isconcealed in each of said thrcc positions of said sealing unit.

11. The combination of claim 1, further comprising concealed sealingelements provided on said one wall member in said groove and beingengaged by said sealing unit in said third position of said sealingunit.

12. The combination of claim 1, wherein said partition has first andsecond end faces, respectively, adjacent to said first and second wallmembers and further comprising sealing liner means provided on at leastone of said end faces and having a width at least approximating thethickness of said partition.

13. The combination of claim 12, wherein said sealing liner meansconsists of elastomeric sound-proofing material.

14. The combination of claim 1, wherein the other of said walls has asecond groove in register with said partition and said partitioncomprises a projection extending into and movable lengthwise of saidsecond groove in said first position of said sealing unit.

15. The combination of claim 14, wherein said partition comprisessealing means engaging said other wall in said second and thirdpositions of said sealing unit.

16. the combination of claim I, wherein said means for moving saidsealing unit comprises a plurality of levers pivotably mounted on saidone wall and coupled to said sealing unit, and means for pivoting saidlevers.

17. The combination of claim 16, wherein said means for pivoting saidlevers comprises an elongated rod coupled to said levers and means formoving said rod lengthwise to thereby pivot said levers.

18. The combination of claim 1, wherein said means for moving saidsealing unit comprises motor means and means for controlling theoperation of said motor means.

19. The combination of claim 18, wherein said motor means includes areversible electric motor and said means for controlling includes limitswitches actuatable in response to movement of said sealing unit to saidfirst and third positions.

20. The combination of claim 18, wherein said means for controllingcomprises a set of pushbuttons or switches.

1. In a room or an analogous enclosure, the combination of an upperfirst wall; a lower second wall; a partition extending between saidwalls, one of said walls having an elongated groove in register withsaid partition; an elongated sealing unit vertically movably installedin said groove; coupling means connecting said sealing unit with saidpartition so as to allow for vertical movement of said sealing unit withand relative to said partition; and means for moving said sealing unitup and down between a first position in which said partition is spacedapart from the other of said walls, a second position in which saidpartition abuts against said other wall, and a third position in whichsaid partition abuts against said other wall and said sealing unit bearsagainst said partition.
 2. The combination of claim 1, wherein saidcoupling means is movable with said partition in the longitudinaldirection of said groove in the first position of said sealing unit. 3.The combination of claim 1, wherein said one wall is said first wall. 4.The combination of claim 3, wherein said sealing unit comprises anelongated carrier having at least one elongated guide member, saidcoupling means being movable with said partition lengthwise of saidguide member in said first position of said sealing unit.
 5. Thecombination of claim 1, wherein said partition has a predeterminedthickness and said sealing unit comprises an elongated carrier and twosealing strips mounted on said carrier and each having a thickness atleast substantially approximating half the thickness of said partition.6. The combination of claim 1, wheRein said one wall includes two panelsflanking said groove and said sealing unit includes an elongated carrierand two elongated sealing strips mounted on said carrier and eachadjacent to one of said panels, said carrier including two plate-likebiasing elements each making an acute angle with the plane of saidpartition and each arranged to urge one of said sealing strips againstthe neighboring panel of said one wall in response to movement of saidsealing unit from said second to said third position thereof.
 7. Thecombination of claim 6, wherein said sealing strips have inclined firstsurfaces abutting against the respective biasing elements and secondsurfaces abutting against said partition in said third position of saidsealing unit.
 8. The combination of claim 1, wherein said sealing unitcomprises an elongated carrier, two sealing strips and means for movablyconnecting said sealing strips to said carrier so as to allow forsidewise movement of said sealing strips against said one wall inresponse to movement of said sealing unit to said third positionthereof.
 9. The combination of claim 1, wherein said partition has firstand second end faces, respectively, adjacent to said first and secondwalls and first and second sealing liners respectively applied to saidfirst and second end faces thereof.
 10. The combination of claim 9,wherein at least one of said liner is concealed in each of said threepositions of said sealing unit.
 11. The combination of claim 1, furthercomprising concealed sealing elements provided on said one wall memberin said groove and being engaged by said sealing unit in said thirdposition of said sealing unit.
 12. The combination of claim 1, whereinsaid partition has first and second end faces, respectively, adjacent tosaid first and second wall members and further comprising sealing linermeans provided on at least one of said end faces and having a width atleast approximating the thickness of said partition.
 13. The combinationof claim 12, wherein said sealing liner means consists of elastomericsound-proofing material.
 14. The combination of claim 1, wherein theother of said walls has a second groove in register with said partitionand said partition comprises a projection extending into and movablelengthwise of said second groove in said first position of said sealingunit.
 15. The combination of claim 14, wherein said partition comprisessealing means engaging said other wall in said second and thirdpositions of said sealing unit.
 16. the combination of claim 1, whereinsaid means for moving said sealing unit comprises a plurality of leverspivotably mounted on said one wall and coupled to said sealing unit, andmeans for pivoting said levers.
 17. The combination of claim 16, whereinsaid means for pivoting said levers comprises an elongated rod coupledto said levers and means for moving said rod lengthwise to thereby pivotsaid levers.
 18. The combination of claim 1, wherein said means formoving said sealing unit comprises motor means and means for controllingthe operation of said motor means.
 19. The combination of claim 18,wherein said motor means includes a reversible electric motor and saidmeans for controlling includes limit switches actuatable in response tomovement of said sealing unit to said first and third positions.
 20. Thecombination of claim 18, wherein said means for controlling comprises aset of pushbuttons or switches.